//
//  WBOAuthViewController.swift
//  MyWeibo
//
//  Created by timw on 2017/3/30.
//  Copyright © 2017年 wuqc. All rights reserved.
//

import UIKit
import SVProgressHUD

/// 通过 webView 加载新浪微博授权页面控制器
class WBOAuthViewController: UIViewController {
    
    private lazy var webView = UIWebView()
    
    override func loadView() {
        view = webView
        
        view.backgroundColor = UIColor.white
        
        // 取消滚动视图
        webView.scrollView.isScrollEnabled = false
        
        //设置代理
        webView.delegate = self
        
        // 设置导航栏
        title = "登录新浪微博"
        
        // 导航栏按钮
        navigationItem.leftBarButtonItem = UIBarButtonItem(title: "返回", target: self, action: #selector(close), isBack: true)
        navigationItem.rightBarButtonItem = UIBarButtonItem(title: "自动填充", target: self, action: #selector(autoFill), isBack: false)
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        // https://api.weibo.com/oauth2/authorize
        // Do any additional setup after loading the view.
        // 加载授权信息
        let urlString = "https://api.weibo.com/oauth2/authorize?client_id=\(WBAppKey)&redirect_uri=\(WBRedirectURI)"
        // 1> URL 确定要访问的资源
        guard let url = URL(string: urlString) else {
            return
        }
        
        // 2> 建立请求
        let request = URLRequest(url: url)
        
        // 3> 加载请求
        webView.loadRequest(request)
    }

    /// MARK - 监听返回
    @objc fileprivate func close() {
        SVProgressHUD.dismiss()
        dismiss(animated: true, completion: nil)
    }
    
    @objc private func autoFill() {
        // 准备js
        let js = "document.getElementById('userId').value='18960315650';" + "document.getElementById('passwd').value='test123'"
        // 让 webview执行js 这里只是修改本地浏览器的页面
        webView.stringByEvaluatingJavaScript(from: js)
        
    }
}

extension WBOAuthViewController: UIWebViewDelegate {

    /// webview 将要加载请求
    ///
    /// - Parameters:
    ///   - webView: webview
    ///   - request: 要加载的请求
    ///   - navigationType: 导航类型
    /// - Returns: 是否加载 request
    func webView(_ webView: UIWebView, shouldStartLoadWith request: URLRequest, navigationType: UIWebViewNavigationType) -> Bool {
        // 确认思路
        // 1.如果请求地址包含http://baidu.com 不加载页面／否则加载页面
        if request.url?.absoluteString.hasPrefix(WBRedirectURI) == false {
            return true
        }
        //print("加载请求 ---\(request.url?.absoluteString)")
        //print("加载请求 ---\(request.url?.query)")
        // 2.从http://baidu.com 回调地址的查询字符串查找code
        // 如果有，授权成功,否则，授权失败
        if request.url?.query?.hasPrefix("code=") == false {
            //print("授权失败")
            close()
            return false
        }
        
        // 3.从query 字符串中取出 授权码
        // 代码走到此处已定有查询字符串，并且包含‘code’
        let code = request.url?.query?.substring(from: "code=".endIndex) ?? ""
        
        print("授权码 - \(code)")
        
        // 4.使用授权吗获取AccessToken
        WBNetworkManager.shared.loadAccessToken(code: code) { (isSuccess) in
            if !isSuccess {
                SVProgressHUD.showInfo(withStatus: "网络请求失败")
            }else {
                SVProgressHUD.showInfo(withStatus: "登录成功")
                
                // 下一步做什么？ 跳转‘界面’ 通过通知发送登录成功消息
                // 1> 发送通知
                NotificationCenter.default.post(
                    name: NSNotification.Name(rawValue: WBUserLoginSuccessedNotification),
                    object: nil)
                
                // 2> 关闭窗口
                self.close()
            }
        }
        
        return false
    }
    
    func webViewDidStartLoad(_ webView: UIWebView) {
        SVProgressHUD.show()
    }
    
    func webViewDidFinishLoad(_ webView: UIWebView) {
        SVProgressHUD.dismiss()
    }
    
}
